Place and Route is a stage in design of integrated circuits at which a layout of a larger block of the circuit or the whole circuit is created from layouts of smaller sub-blocks. With large sizes of modern designs, this operation is usually performed by electronic design automation (EDA) tools.
Types of blocks and the process itself depend on design methodology. Due to the complexity of the task, it is usually performed in two separate stages, placement , i.e., determining the positions of the sub-blocks in the design area, and routing , i.e., interconnecting the sub-blocks. Recently (as of 2004) there are attempts to combine the two tasks back into one.